<?php
namespace erweima;

class CreatePoster{

	
	public static function draw($config=array(), $filename=""){
		//如果要看报什么错，可以先注释调这个header
		  if (empty($filename)) {
		      header("content-type: image/png");
		  }
		  $imageDefault = array(
		  'left'=>0,
		  'top'=>0,
		  'right'=>0,
		  'bottom'=>5,
		  'width'=>0,
		  'height'=>0,
		  'opacity'=>100
		);
		  $textDefault = array(
		  'text'=>'',
		  'left'=>0,
		  'top'=>0,
		  'fontSize'=>32,       //字号
		  'fontColor'=>'255,255,255', //字体颜色
		  'angle'=>0,
		);
		  $background = $config['background'];//海报最底层得背景
		  //背景方法
		  $backgroundInfo = \getimagesize($background);
		  $backgroundFun = 'imagecreatefrom'.image_type_to_extension($backgroundInfo[2], false);
		  $background = $backgroundFun($background);
		  $backgroundWidth = imagesx($background);  //背景宽度
		$backgroundHeight = imagesy($background);  //背景高度
		$imageRes = imageCreatetruecolor($backgroundWidth, $backgroundHeight);
		  $color = imagecolorallocate($imageRes, 0, 0, 0);
		  imagefill($imageRes, 0, 0, $color);
		  // imageColorTransparent($imageRes, $color);  //颜色透明
		  imagecopyresampled($imageRes, $background, 0, 0, 0, 0, imagesx($background), imagesy($background), imagesx($background), imagesy($background));
		  //处理了图片
		  if (!empty($config['image'])) {
		      foreach ($config['image'] as $key => $val) {
		          $val = array_merge($imageDefault, $val);
		          $info = getimagesize($val['url']);
		          $function = 'imagecreatefrom'.image_type_to_extension($info[2], false);
		          if ($val['stream']) {   //如果传的是字符串图像流
		              $info = getimagesizefromstring($val['url']);
		              $function = 'imagecreatefromstring';
		          }
		          $res = $function($val['url']);
		          $resWidth = $info[0];
		          $resHeight = $info[1];
		          //建立画板 ，缩放图片至指定尺寸
		          $canvas=imagecreatetruecolor($val['width'], $val['height']);
		          imagefill($canvas, 0, 0, $color);
		          //关键函数，参数（目标资源，源，目标资源的开始坐标x,y, 源资源的开始坐标x,y,目标资源的宽高w,h,源资源的宽高w,h）
		          imagecopyresampled($canvas, $res, 0, 0, 0, 0, $val['width'], $val['height'], $resWidth, $resHeight);
		          $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']) - $val['width']:$val['left'];
		          $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']) - $val['height']:$val['top'];
		          //放置图像
		    imagecopymerge($imageRes, $canvas, $val['left'], $val['top'], $val['right'], $val['bottom'], $val['width'], $val['height'], $val['opacity']);//左，上，右，下，宽度，高度，透明度
		      }
		  }
		  //处理文字
		  if (!empty($config['text'])) {
		      foreach ($config['text'] as $key => $val) {
		          $val = array_merge($textDefault, $val);
		          list($R, $G, $B) = explode(',', $val['fontColor']);
		          $fontColor = imagecolorallocate($imageRes, $R, $G, $B);
		          $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']):$val['left'];
		          $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']):$val['top'];
		          imagettftext($imageRes, $val['fontSize'], $val['angle'], $val['left'], $val['top'], $fontColor, $val['fontPath'], $val['text']);
		      }
		  }
		  //生成图片
		  if (!empty($filename)) {
		      $res = imagejpeg($imageRes, $filename, 90); //保存到本地
		      imagedestroy($imageRes);
		      if (!$res) {
		          return false;
		      }
		      return $filename;
		  } else {
		      imagejpeg($imageRes);     //在浏览器上显示
		      imagedestroy($imageRes);
		  }
		
	}
}